Plastic bakery trays include a base and side walls extending upward from side edges of the base. Front and rear walls are often shorter than the side walls to provide access to the baked goods (or other items) in the trays when they are loaded and stacked.
When loaded and stacked, the trays are supported on one another on the side walls, with the base and front and rear walls suspended from one side wall to the other. If a stack of loaded trays are moved by means of a hand truck, the blade of the hand truck may be inserted under the base, in the center of the front or rear walls. This may cause the center of the trays to deflect upward.